Now a day's one of the major problems in construction industries is insufficient and unavailability of construction materials, on the other side the main environmental problem is the disposal of the waste plastics. In this experimental study, an attempt has been made to use the plastics in concrete and studies have been conducted to focus on the Stress Strain Behaviour of plastic mix concrete and compared with Stress Strain Behaviour of conventional concrete Two types of plastics namely polythene sheets and plastic straws were selected and mixed with concrete in various proportions (0.5%, 1.0% & 1.5%). The use of plastics in various places as packing materials and the products such as bottle, polythene sheet, containers packing strips etc,. are increasing day by day. This results in production of plastic waste from all sort of livings from industrial manufacturers to domestic users. So, we are in need to search for new construction materials as well as a method to dispose the plastic waste.